Screening And Identificationof Probiotics And Its Preliminary Studyonthe Effectofe.carinata

Probiotics are widely used in livestock and poultry farming,but few studies have been reported in special breed animals,especially in snake farming.In order to explore the effects of probiotics on snakes,this project screened probiotics and used the artificially bredE.carinata as the research object to carry out a 42-day feeding experiment,laying a theoretical foundation for the promotion and application of probiotics in the snake breeding industry.One probiotic was selected from 4 strains of probiotics,and the probiotics were tested for abnormal toxicity,safety,digestive tolerance and drug susceptibility.The bacteria were identified by phenotypic examination and 16s rDNA sequencing.The probiotic liquid was obtained by univariate variable method and orthogonal test optimization.The probiotic liquid with a concentration of 108 cfu/mL was fed to the test snake at a dose of 1 mL/100 g weight,and fecal samples and blood samples were collected for physiological and biochemical indicators such as intestinal flora,protein,total white blood cells,urea nitrogen and superoxide dismutase.The results are as follows:1.A probiotic strain that meets the requirements was selected as Bacillus licheniformis.2.Bacillus licheniformis optimized medium group was peptone lOg/L,beef extract 15g/L,yeast powder 3g/L,potassium dihydrogen phosphate 2g/L;optimal culture conditions were 37?,pH 7.2,shaking speed of 200 rpm,and cultured for 10 hours.The content of Escherichia coli and Clostridium perfringens in the experimental group of probiotics was lower than that of the control group.The content of Enterococcus faecalis was higher than that of the control group,and the content of fecal protein was lower than that of the control group.Compared with the control group,the total bilirubin and malondialdehyde content in the blood,the activity of alanine aminotransferase decreasedof the experimental group.and the activity of total superoxide dismutase and glutathione peroxidase in the blood increased.The above indicators were significantly different(P<0.05).Compared with the control group,the average daily weight gain of the experimental group E.carinata was higher,the total number of peripheral white blood cells increased,the activity of alkaline phosphatase and aspartate aminotransferase in the blood decreased,and uric acid,urea nitrogen,creatinine,cholesterol and glycerol in the blood decreased.;however,the differences were not significant,and the effect on various cell contents in white blood cells was not significant,either.(P>0.05).Conclusion:Bacillus licheniformis is a probiotic suitable for E.carinata application.The bacteria does not affect the health of E.carinata.It has a certain promoting effect on growth,improve the conversion rate of feed and reduce the taste of feces,and lay a certain foundation for the promotion and deep application of probiotics on E.carinata.